P554 Statistics in Psych, Prof. Kruschke

P554 Statistics in Psychology, Prof. Kruschke
Lab Assignment for Ch. 13. Th-F 12-13 Apr 2007.

General instructions. This assignment is to be done in your lab session. Submit your assignment from the lab computer during lab time. If the assignment involves SPSS, be sure that when you open SPSS, you set it so that commands are displayed in the output: Edit -> Options, Viewer tab, check box Display commands in the log.

Load this Excel spreadsheet. Notice that it reproduces the results from Table 13.2 from the textbook.

  • Change the definition of D2.
    * Copy the worksheet to another worksheet: On the worksheet tab at the bottom of the spreadsheet, right click and select Move or Copy from the menu. In the dialogue box, make sure to check the checkbox for Make a copy. After the copy is made, right click its tab and rename this second worksheet as "Different D2".
    * Under D2, in cell G4, type a new formula for D2: "=D4-((B4+C4)/2)". Copy the formula in all the D2 cells, from G4 to G11.
    * Compared with the original spreadsheet, what has happened to the F ratio for the multivariate omnibus test? Why? Type your answer as an inserted textbox on the spreadsheet.
    * Is the mean of Y3 significantly different from the average of Y1 and Y2? What tells you the answer? Type your answer as an inserted textbox on the spreadsheet.

  • Change the AxS interaction.
    * Copy the ORIGINAL worksheet to another worksheet: On the worksheet tab at the bottom of the spreadsheet, right click and select Move or Copy from the menu. In the dialogue box, make sure to check the checkbox for Make a copy. After the copy is made, right click its tab and rename this second worksheet as "Different AxS".
    * Sort the data in Y1 column from smallest to largest: Select B4:B11, then (in Excel 1007) click Home -> Sort -> Smallest to Largest -> Continue with current selection [NOT expand selection]. Sort the data in the Y2 column from largest to smallest. Sort the data in the Y3 column from smallest to largest.
    * Compared with the original spreadsheet, what has happened to the F ratio for the multivariate omnibus test? Why? Type your answer as an inserted textbox on the spreadsheet.
    * Is the difference between the mean of Y2 and the mean of Y1 significant? How about between Y3 and Y2? How does that compare with the original data? Why? Type your answer as an inserted textbox on the spreadsheet.

    Save a copy of your work for your records, and upload a copy to the Assignments in Oncourse.